[Objective] The effects of short-duration high-intensity rainfall on runoff and sediment yield in a karst slope farmland were analysed to reveal the mechanism of soil erosion, in order provide a scientific basis for reducing it, and ensuring food production in karst slope farmlands. [Methods] Through simulated rainfall experiments, the effects of short-duration high-intensity rainfall on the runoff and sediment yields over a karst slope farmland were studied by taking a karst bare slope and a corn slope as research objects. [Results] ① Surface runoff and sediment yield moduli of both bare and corn slopes increased with the rise of the slope. At similar slopes, the surface runoff and sediment yield moduli of the corn slope were much less than those of the bare slope (p＜0.05). With the increase of rainfall duration, the surface runoff yield moduli of both bare and corn slopes increased first and then remained stable, while the surface sediment yield moduli increased first and then decreased. ② The runoff yield moduli of the respective subsurface runoffs of bare and corn slopes increased with the rise of the slope. At a similar slope, the runoff yield of respective subsurface runoffs in the corn slope was much less than that in the bare slope (p＜0.05), whereas when slope was 20°, the total runoff yield of the corn slope’s subsurface runoffs (15—25 cm) decreased by 62.59% compared with that of the bare slope. ③ When the slope was fixed, underground runoff and sediment yield moduli of the corn slope were much less than those of the bare slope (p＜0.05). With the increase of rainfall duration, the underground runoff yield moduli of both bare and corn slopes showed a trend of continuous increase, where their changes were basically consistent, while the underground sediment yield moduli showed a trend of first increasing and then decreasing and reached a maximum between 20 min and 30 min. ④ By comparing the correlations between the runoff and sediment yields of the bare and the corn slopes under different slopes, it was found that the correlations between the underground sediment yield and the surface runoff yield, underground runoff yield, and surface sediment yield were enhanced in the corn slope compared with the bare slope, whereas the correlations between the surface sediment yield and the surface and underground runoff yields were weakened. [Conclusion] Under high-intensity rainfall, corn slope can increase infiltration, which has the effect of blocking and inhibiting erosion, in which the surface and subsurface runoff moduli increase with the increase of the slope, the underground runoff moduli increase with the increase of the rainfall duration, and the sediment yield moduli increases first and then decreases.